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    Subject[ 045/149] ntp: Fix integer overflow when setting time
    3.2-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Sasha Levin <levinsasha928@gmail.com>

    commit a078c6d0e6288fad6d83fb6d5edd91ddb7b6ab33 upstream.

    'long secs' is passed as divisor to div_s64, which accepts a 32bit
    divisor. On 64bit machines that value is trimmed back from 8 bytes
    back to 4, causing a divide by zero when the number is bigger than
    (1 << 32) - 1 and all 32 lower bits are 0.

    Use div64_long() instead.

    Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
    Cc: johnstul@us.ibm.com
    Link: http://lkml.kernel.org/r/1331829374-31543-2-git-send-email-levinsasha928@gmail.com
    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    kernel/time/ntp.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/kernel/time/ntp.c
    +++ b/kernel/time/ntp.c
    @@ -275,7 +275,7 @@ static inline s64 ntp_update_offset_fll(

    time_status |= STA_MODE;

    - return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs);
    + return div64_long(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs);
    }

    static void ntp_update_offset(long offset)



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